Good news. Google Dance isn't a term you really need to concern yourself with anymore, because they just don't happen anymore. It's one of those legacy terms.

Back in the day Google used to update its index on a roughly monthly basis. Meaning they would completely rebuild their index each month. During this rebuild site rankings would often jump all over the place over the course of several days, hence the term Google Dance.

Google doesn't do this anymore. Nowadays they're updating constantly, every single day. So while there is movement more often it's not nearly as pronounced as it was in the past.

About the only time you see something that resembles the old Google Dances is when Google takes it upon themselves to do a total index rebuild, usually when they're making some major changes in their algorithm that stand a good chance of shaking things up a bit. We only see those 2-3 times per year, as opposed to every month.